This is a sexual act involving cumming on the insides of a girl ankles. Then proceed to push the feet together until they stick. When this is completed and both feet are stuck together slap her in the face and throw seaweed at her. This should give her the appereance of an angry mermaid

John: Hey man i angry mermaided this bitches ass last night
Gary: No way man! whered you get the seaweed?
John: Your momma gave it to me after I Boned her!

a sexual act in which two males and one female go scuba diving. While underwater each male releases into a chosen ear of the female. At this point the female descends to a lower depth in the water and releases the pressure from her ears. This creates cloudy water; therefore giving the appearance of an angry mermaid. This is a difficult maneuver to achieve; however if it is executed properly maximum pleasure can be attained.

the angry mermaid is not to be attempted by the underskilled...experts only!